iPhone and iPad auto correct in multiple languages

If you need to type in your iPhone or iPad in multiple languages it is possible to use the auto correct feature in the correct idiom.
All you have to do is choose the keyboard for the language you want to type - auto correct will choose the dictionary based on the current keyboard.

To add a keyboard go to Settings > General > Keyboard > International Keyboards > Add new Keyboard... and choose the language you want to add.